Detective Chief Superintendent Colin Field, of Strathclyde Police's major crime and terrorism investigation unit, said: "This is a very good example of the police making the best use of their information and intelligence resources to take pre-emptive action."

Strathclyde Police issued 336 warnings in 2009-10 compared with 55 in 2004-5. But the number was down from 452 in 2008-9. Fife Constabulary issued five warnings in 2009-10 and Lothian and Borders Police three.

The remaining five Scottish forces either issued no warnings or were unable to provide figures.

Among those issued with Osmans in recent years were security industry boss Bobby Dempster and former UDA chief Johnny Adair.

The warnings were introduced after English teenager Ahmet Osman was shot and wounded by Paul Paget-Lewis in 1988.

Judges found police officers knew about the psychotic teacher's obsession with Osman but failed to warn and protect him.